mclellan



(No Model.) 2 Sheets-Sheet; 1,

R. A. MOLELLAN.

ENGINE VALVE GEAR.

No. 349,512. Patented Sept. 21, 1886.

(No Model.) 2 Sheets-She'et 2.

R. A. MoLELLAN.

ENGINE VALVE GEAR.

No. 349,512. Patented Sept. 21, 1886.

.UNITED STATES PATENT OFFICE.

ROBERT A. MOLELLAN, or SAN FRANCISCO, OALIFOR'NIAr ENGINE-VALVE GEAR.

SPECIFICATION forming part of Letters Patent No. 349,512, datedSeptember 21, 1886.

Application filed June 11, 1886. Serial No. 204,875. (No model.)

one of thesteam and one of the exhaust valves.

Figs. 2 and 3 are side views of the eccentrics and links. Fig. 4 is arear view of the links.

Ais the bed of the engine; 13, the cylinder; 0, th e crank wheel ordisk; and D D are eccentrics having the eccentric-rods E and F, asshown.

G is a rocker-arm having its upper end pivoted or fulcrumed at H to theupper end of a lever, L, which is fulcrumed at the center, and

from its lower end 'a rod, I, extends to the rockershaft J, which bysuitable connections aetuates the exhaust-valves of the engine.

The eccentric-rod E is hooked or otherwise connected with the arm G bymeans of a pin, K, which is fixed to the arm, the eccentric whichactuates this being set at one hundred and thirty-five degreesin advanceof the crank.

The eccentric-rod F connects with a rockerarm, L, fulcrumed at thecenter, and the rod M connects the arm Gwith the rocker-arm N, which iscentrally fulcrumed upon the framework of the engine, the rod Mconnecting its lower end and the rod 0 connecting its upper end with therocker-arms P, which serve to lift the valves. The upper end 'of theswinging arm G is slotted, as shown at G, and the end of the arm M isconnected with a block which slides in the slot.

The governor a "may be of any well-known or desired form, and isconnected by a rod, 1),

with the rod M, so that when the speed of the engine increases the endof the rod will be drawn upward in the slot in the arm G, so that it andthe valves will be moved to close the valves quicker. \Vhen the enginemoves slower, the opposite result takes place.

The valves are of the ordinary puppet form, as shown at Q, and the stemsR connect with the vertically-moving frame S, which is slotted so as toreceive the outer end of the arm T. This arm is fulcruined upon astandard, as shown at U, and the toes V, which are con nected with theshaft or rocker-arm I, act to lift the lever T, and with it the guideand valve stem. The valves are set very close to the passages in thecylinder, so that there is the least possible lost space at this point.The construction of the levers T is such that the toes V commence actingupon them at the outer or free end, so that they have the most power toraise the valve from its seat when they first begin to act, and afterthis result is attained the valve will be lifted almost instantaneouslythe remainder of the distance, so that it is open to its full amountvery shortly after the piston commences its movement in the cylinder.

The operation of this gear is as follows: The eccentric which moves therod F is set to move with' the crank-pin, and the eccentric which drivesthe rod E is set one hundred and thirtyfive degrees in advance of thecrank. The rod F connects with the lower end of the centrallyfulcrumedlever L, and the rod E with the center of the arm G, the'upper end ofwhich is journaled to the upper end of L, so that it receives theresultant motion due to the action of the two eccentrics, and thismotion is communicated to the rod M and valves, as before described.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. A lever centrally fulcrumed to the frame and having its lower endconnected with an eccentric in a radial plane with the crank, and asecond lever, the upper end of which is suspended from the upper end ofthe first and its center connected with a second eccentric set inadvance of the crank, in combination with a rod adjustable upon thesecond lever and connected with the steam-admission valves,substantially as herein described.

2. Alever centrally fulcrumed to the engineframe and having its lowerend connected with an eccentric upon the engine-shaft, and a secondlever fulcrumed to the upper end of the first one, with its centralportion connected with a second eccentric set at an angle with the firstone, and the lower end of the second lever connected by a rod with theexhaustvalve, in links G and L, the eccentrics connected withcombination with a rod adj ustably connecting them, and a governorwhereby the connections the upper end of the second swinging lever ofthe valve-lifting toe with the link is regu- With the steam-admissionvalves and a govlated by the engine-speed, substantially as [5 5 ernorby which the position of the rod is deherein described.

termined, substantially as herein described. In witness whereof I havehereunto set my 3. The steam-valve with the vertical stein, hand. thelever connected with the stem at one end ROBERT A. MQLELLAN. and havingthe opposite end fulcrnmed, as Witnesses: 10 shown, and an oscillatinglifting arm or toe act 0. 1). COLE,

ing upon the lever, in combination with the J. H. BLOOD.

